<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css">
		.box{
			width: 420px;
			height: 400px;
			margin: 0 auto;
			margin-top: 100px;
		}
		.left{
			float: left;
		}
		.son{
			width: 200px;
			height: 200px;
			background: blue url() 0 0 no-repeat;
			margin-bottom: 20px;
			
		}
		.right{
			width: 200px;
			height: 420px;
			background: red url() 0 0 no-repeat;
			float: right;
			margin-left: 20px;
		}
	</style>
</head>
<body>
	<div class="box">
		<div class="left">
			<div class="son">200*200</div>
			<div class="son">200*200</div>
		</div>
		<div class="right">200*400</div>
	</div>
</body>
</html>